#include "stdio.h"

#include "math.h"

double fo(double w);

double fw(double o);

int main(int argc, char const *argv[]) {

double tf = 10, t0, dt;

double g = 9.8, l = 1, ko, kw;

double o0 = M_PI/4, w0 = 0, o1, w1;

int n = 100000;

dt = (tf - t0)/n;

printf("t\ttheta\tomega\n");

printf("%f\t%f\t%f\n", t0, o0, w0);

while (t0 <= tf) {

ko = fo(w0);

kw = fw(o0);

o1 = o0 + dt*fo(w0 + 0.5*dt*ko);

w1 = w0 - dt*fw(o0 + 0.5*dt*kw);

o0 = o1;

w0 = w1;

t0 += dt;

printf("%f\t%f\t%f\n", t0, o0, w0);

}

return 0;

}

double fo(double w) {

return w;

}

double fw(double o) {

return -9.8*sin(o);

}